According to the state of technology, the idle wheels used as cog wheels in transmissions with two countershafts are radially guided into both gearings of the countershafts. The cog wheels are guided on the main shaft in the axial direction by the washer disks, whereby a washer disk of the idler wheel is placed between two washer disks on the main shaft. There thus results the disadvantage that relatively large plays are caused by the work tolerances and the opening required for oil lubrication, so that when the loads of the idler wheels are stimulated because of the swaying movements of the main shaft or the oscillating rotary motion, an unpleasant rattling noise arises.
Within the scope of the EP 0361 686 A1, a transmission with a countershaft is proposed where the countershaft gear wheel of the driving mechanism constant is arranged on the countershaft in such manner that the oscillations of the gear wheel are not transmitted to the countershaft because of a small play arising therefrom as well as because of a dampening element connected to the gear wheel and placed parallel to the countershaft in order that, in this manner, the rattling noise is suppressed as much as possible. This design, however, has proven to be very costly and, furthermore, the vibration noises cannot be fully suppressed, since the additional wheels arranged on the countershaft would be interfering with the corresponding idler wheels of the drive shaft unless additional construction measures were undertaken.
The task of the invention is to provide a device to prevent the swaying of the cog wheels arranged on the main shaft or, as the case may be, to avoid the above noted vibration noises in a power train with two countershafts.